In this Feb. 12, 2018, file photo, Environmental Protection Agency Administrator Scott Pruitt attends a meeting with state and local officials in the State Dining Room of the White House in Washington. Pruitt and his staffers took nearly $150,000 in commercial and charter flights over seven-months last year, including repeated trips to Pruitt’s home state of Oklahoma, according to travel vouchers obtained by an environmental group.

SAN FRANCISCO — Environmental Protection Agency administrator Scott Pruitt and staffers billed taxpayers nearly $200,000 for his trips over six months last year, according to travel vouchers obtained by an environmental organization.

Pruitt is one of several Trump administration officials who have drawn attention over travel costs, including Pruitt’s frequent travel at first-class rates. Pruitt earlier this week said a “toxic environment politically” required first-class travel and protection from a 24-hour security detail.

The Environmental Integrity Project environmental group obtained the travel vouchers, which cover trips by Pruitt and 14 staffers from March to August, through open-records requests. Previous vouchers acquired by the group covered the EPA chief’s travel over a shorter period.

Pruitt is a former Oklahoma attorney general and longtime Tulsa-area resident. Most of at least 10 expensed trips involving stops in his home state of Oklahoma were into the Tulsa airport, including for events in or closer to Oklahoma City, the state’s capital and site of the biggest state airport.

Vouchers released for some of the Oklahoma trips cited the reason for travel only as “meetings in state” or as tours of companies in the Tulsa area.

Eric Schaeffer, founder of the group that obtained the records, called the justifications for some of the trips back home “a little squirrelly.”

“You can’t do what you can do as maybe a corporate lawyer,” as head of the EPA, Schaeffer said. “You’re putting one meeting on the calendar so it’s official business.”

Jahan Wilcox, an EPA spokesman, said he had no immediate comment on the six months of travel costs. A handful of the travel reports for Oklahoma trips said routing trips to multiple destinations through Tulsa was as affordable as a more direct route, or said Pruitt or another party had picked up some or all of the costs.

The effects of the longest government shutdown in U.S. history continue to ripple across Colorado, with businesses near Rocky Mountain National Park reporting losses and furloughed federal workers applying for unemployment benefits.